Commit 0d81092a authored by Lee, Chun-Yi's avatar Lee, Chun-Yi Committed by Wang Yufen
Browse files

Bluetooth: hci_ldisc: check HCI_UART_PROTO_READY flag in HCIUARTGETPROTO 

mainline inclusion
from mainline-v6.6-rc1
commit 9c33663a
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/I6YOAU
CVE: CVE-2023-31083

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=9c33663af9ad115f90c076a1828129a3fbadea98



--------------------------------

This patch adds code to check HCI_UART_PROTO_READY flag before
accessing hci_uart->proto. It fixes the race condition in
hci_uart_tty_ioctl() between HCIUARTSETPROTO and HCIUARTGETPROTO.
This issue bug found by Yu Hao and Weiteng Chen:

BUG: general protection fault in hci_uart_tty_ioctl [1]

The information of C reproducer can also reference the link [2]

Reported-by: default avatarYu Hao <yhao016@ucr.edu>
Closes: https://lore.kernel.org/all/CA+UBctC3p49aTgzbVgkSZ2+TQcqq4fPDO7yZitFT5uBPDeCO2g@mail.gmail.com/

 [1]
Reported-by: default avatarWeiteng Chen <wchen130@ucr.edu>
Closes: https://lore.kernel.org/lkml/CA+UBctDPEvHdkHMwD340=n02rh+jNRJNNQ5LBZNA+Wm4Keh2ow@mail.gmail.com/T/

 [2]
Signed-off-by: default avatar"Lee, Chun-Yi" <jlee@suse.com>
Signed-off-by: default avatarLuiz Augusto von Dentz <luiz.von.dentz@intel.com>
Signed-off-by: default avatarWang Yufen <wangyufen@huawei.com>
parent d67a9a26

drivers/bluetooth/hci_ldisc.c

+2 −1
Original line number Diff line number Diff line
@@ -772,7 +772,8 @@ static int hci_uart_tty_ioctl(struct tty_struct *tty, struct file *file, 
		break;



	case HCIUARTGETPROTO:

		if (test_bit(HCI_UART_PROTO_SET, &hu->flags))

		if (test_bit(HCI_UART_PROTO_SET, &hu->flags) &&

		    test_bit(HCI_UART_PROTO_READY, &hu->flags))

			err = hu->proto->id;

		else

			err = -EUNATCH;